Renal Function Test Flashcards
The standard tests used to measure the filtering capacity of the glomeruli
Clearance test
Stability of substance in urine during 24- hour urine collection
Clearance test
Clearance test Reported in
mL/min
STANDARD METHOD for GFR
Urea clearance test
Demonstrate progression of renal
disease or response to therapy
Urea clearance test
REFERENCE METHOD for GFR
Inulin clearance test
Not routinely done because of the necessity for
continuous IV infusion
Inulin clearance test
Inulin clearance test PRIMING DOSE:
25ml of 10% inulin solution
Inulin clearance test CONTINUOUS INFUSION:
500ml of 1.5% inulin solution
Inulin clearance test
REFERENCE VALUES: male
127 ml/min
Inulin clearance test
REFERENCE VALUES: female
118 ml/min
Most commonly used; screening method of GFR
Creatinine clearance
waste product of muscle metabolism
Creatinine clearance test
Creatinine clearance
REFERENCE VALUES: Male
◦ 75- 112 mL/ min Female
85-125 mL/ min
Creatinine clearance
REFERENCE VALUES: Female
75- 112 mL/ min
Standard body surface
1.73 m2
Creatinine clearance MINUTES
1440 mins
Indirect estimate of GFR
Cystatin C
Completely reabsorbed by the PCT, hence its
presence in urine denotes damage to the
tubules
Cystatin C
good procedure for screening and monitoring
GFR.
Cystatin C
Cystatin C specimen
Serum or plasma (not fasting)
Cystatin C increase level
Acute and chronic renal failure
Cystatin C method
Immunoassay
Dissociates from human leukocyte antigens
at constant rate and is rapidly removed
from the plasma by glomerular filtration.
Beta 2 microglobulin
A rise has been shown to be more sensitive
indicator of decrease in GFR than
creatinine clearance
Beta 2 microglobulin
Not reliable in patients who have history of
immunologic disorders.
Beta 2 microglobulin
Beta 2 microglobulin method
Enzyme immunoassay
monitor patients already diagnosed with renal disease or at
risk for renal disease.
Estimated glomerular filtration rate
the formulas are valuable when medications that require
adequate renal clearance need to be prescribed
Estimated glomerular filtration rate
Stages of Chronic Kidney Disease : Kidney Damage with Normal
or high GFR
GFR:
> 90
Stages of Chronic Kidney Disease : Kidney Damage with Mild decrease
GFR
Gfr:
60- 89
Stages of Chronic Kidney Disease : Moderate decrease GFR
Gfr:
30-59
Stages of Chronic Kidney Disease: Severe decrease GFR
Gfr:
15-29
Stages of Chronic Kidney Disease : Kidney Failure
Gfr:
<15 - dialysis
Ability of the tubules to reabsorb the essential
salts and water that have been nonselectively
filtered by glomerulus
Concentration test
specific gravity of urine before entering
the renal tubules, will vary when the urine
enters the renal tubules for the reabsorption
process.
1.010
Patients were deprived of fluids for 24 hours prior to
measuring specific gravity
Fishberg test
Compare the volume and specific gravity of urine of
day and night urine samples
Mosenthal test
specific gravity is influenced by the
number and density (molecular weight)
of the particles.
Osmolality
FREEZING POINT OSMOMETERS
Principle:
Freezing point depression
Temperature at which water and ice are in
equilibrium and is related to solute
concentration
Freezing point
Freezing point osmometer standard reference:
Sodium chloride
VAPOR PRESSURE OSMOMETERS
Principle:
Measure dew point
VAPOR PRESSURE OSMOMETERS
Standard reference
Sodium chloride
VAPOR PRESSURE OSMOMETERS
Standard reference
Sodium chloride
test most commonly associated with tubular
secretion and renal blood flow
P-aminohippuric acid test
The inability to produce an acid urine
in the presence of
metabolic acidosis
Renal tubular acidosis
